1. Field of the Invention
This invention relates to an improved means of mounting bottom fed, side ejecting fuel injectors (like the gaseous type presently made by Servo-Jet of San Diego, Calif.) to the air inlet of an internal combustion engine.
2. Prior Art
The predominate means of adapting gasoline and diesel engines to operate on gaseous fuels has been through the utilization of gaseous carburetors or mixers placed upstream of the liquid fuel induction systems. Gas carburetors have offered the advantage of allowing a wide variety of liquid fueled engines to be operated on gaseous fuels with a minimum amount of labor and re-calibration. This conversion method has the benefit of being relatively simple to install, but fails to deliver the precise fuel delivery offered by digitally controlled fuel injection. The development of digital engine controls for gasoline engines has led to their adaptation to gaseous fuels such as natural gas and propane, which offer improved potential for reducing undesirable exhaust emissions. Methods of adapting gaseous fuel injectors to internal combustion engines have included the employment of cumbersome mixing devices for diffusing fuel ejected from gaseous injectors into the incoming air upstream of a throttle body, or adapters installed beneath the throttle body as well as individual port fuel injection. This task has been complicated by the necessity of employing relatively high fuel pressures for gaseous fuel injection in comparison to the lower pressure of gasoline systems, which has led to the use of bottom fed-side ejecting solenoid valves with their associated awkward feed and delivery conduits.
The present invention consists of a fuel injector fuel supply manifold that positions one or more bottom fed- side ejecting gaseous fuel injectors upstream of the inlet of an engine so as to direct fuel ejected from the injectors through sections of tubing to optimal points near the engine inlet. One or more injectors mounted to this supply manifold may be dedicated to metering fuel through a length of tube into the idle air control (IAC) valve circuit of a throttle body at idle power.
The prime object and advantage of the present invention is to provide the simplest and most economical means of adapting gaseous fuel injection to a gasoline or diesel engine while offering an easier installation method than the previous carburetor and injector conversion technologies. Another object and advantage of this invention is to provide a simple means of adding dual or bi-fuel capability to an engine in a way that facilitates rapid switching between either gaseous or liquid fuel, through the employment of two sets of electrically controlled fuel injectors.
An advantage of the present invention is that by placing the injectors upstream of the engine inlet as opposed to placing them in close proximity to the cylinder heads, as with port injection, they are insulated from the heat of the engine and cooled by the incoming air charge. By maintaining the injectors and gaseous fuel at the same temperature as the incoming air, the need to compensate the quantity of the injected fuel for heat induced changes in mass is greatly reduced or eliminated. A fourth object and advantage of this invention is to provide a means of injecting fuel into an engine throttle body or inlet duct that will cool and enhance the flow of accompanying air, thereby increasing the power and efficiency of the engine. A fifth objective is to provide a means of utilizing one or more fuel injectors of optimal size to inject fuel into the idle air control throttle bypass circuitry of a throttle body in order to reduce noise and improve engine idle quality through increased fuel/air homogeneity and lengthened fuel injector pulse width. The means of accomplishing these objects with their accompanying advantages will be apparent from the following description and drawing.